From SciFi.com:

Andrew Stanton, who is writing and directing John Carter of Mars, based on Edgar Rice Burroughs' books, told SCI FI Wire that he and co-writer Mark Andrews will be putting their own spin on the iconic story, and a Pixar manager added that the film will have a unique look as well.
"I'm going to do what I remember more than what they exactly do" in the books, Stanton said cryptically in a group interview at the Emeryville, Calif., headquarters of Pixar on Sept. 25.
Stanton (WALL*E) added that he is currently deep in writing with partner Andrews, a storyboard artist at Pixar, on the script for Carter. "John Carter of Mars is what I'm writing right now with Mark Andrews," Stanton said. "Writing, it's all about writing this year."
Jim Morris, general manager at Pixar Animation, promised that the movie will not look like previous attempts to adapt the franchise for the screen. "Everything that's been out there has been an attempt to kind of capture this Deco-esque [Frank] Frazetta vision of John Carter, which I think feels old and stale," he said. "And where Stanton is going--from what we've seen so far--is very different than that. And I think that the people who really love the essence of the books will really dig it, but so will audiences in general."
Asked whether the film would be in 3-D, Morris added, "I hope not!"
The film is based on the early-20th-century Barsoom series of books by Burroughs, the California author of the Tarzan series. It centers on a Civil War veteran who finds himself transported to the Red Planet and caught up in various battles and intrigues involving giant green creatures and an alluring princess.
It's been reported that Carter may incorporate live-action elements amid animation. Stanton's WALL*E was the first Pixar production to incorporate live action. Morris declined to discuss the matter.
"John Carter is in its very early stages, and there is much to figure out about that, so we'd be premature," Morris said. "We are looking at a variety of different approaches and techniques for that ... We're kind of a bit early in the development of that."
Morris added: "I'm sure I speak for all of the science fiction geeks, fans and aficionados when I say it's finally time to see that movie. And I, for one, am delighted that Andrew Stanton is the guy that's making the movie, because he's a story-driven guy." --Patrick Lee, News Editor